The invention is directed to an apparatus and a method for surveying and analyzing flow signals that can be picked up by means of flow measuring arrangements in the flow through breathing gas supply systems, in particular CPAP devices, air humidifiers, breathing gas lines, and breathing masks.
For treating sleep-related breathing problems, it is known for a person who is to be treated to be supplied with a breathable gas, especially ambient air, at a pressure level that is above the ambient pressure level. The delivery of the breathing gas is typically done using an rpm-controlled blower. By delivering the breathing gas at a pressure level that is above the ambient pressure, it becomes possible to bring about a so-called pneumatic tracking effect in the upper airway region of the person to be treated, as a result of which obstructions in this airway region can be effectively prevented. The devices provided for pumping the breathing gas, in particular the ambient air, up to the elevated pressure level required for achieving the pneumatic tracking effect typically include a basic unit, in which a blower, intended for pumping the breathing gas, the electronics needed for triggering the blower, and typically also an air humidifier are provided. Carrying the breathing gas pumped through this basic unit to the patient to be treated is done via flexible tubing and a patient interface, e.g., a breathing mask, applied to the patient and coupled to the flexible tubing.
Typically, the basic units provided for pumping the breathing gas are designed such that they survey measurement signals indicative at least of the breathing gas flow and take them into account in regulating the pumping power of the blower.
Particularly, in relatively sensitive online or offline evaluation of the measurement signals surveyed by the flow sensors provided in the unit, it is possible that in the unit, the instantaneous physiological status of the patient is assessed imprecisely or inaccurately, and the breathing gas pressure ascertained on the basis of this imprecise or inaccurate assessment fails to take adequate account of the physiological needs of the patient.